Dielectric properties and aging of fast-fired barium titanate

The dielectric properties and their aging rate of three chemically prepared BaTiO3 Compositions, from Ba-rich to Ti-rich fast fired to 1450degreesC, were measured from 470 K down to 225 K. Ba-rich samples, in spite of their similar sintering behavior when compared to stoichiometric samples, exhibited the highest dielectric constant values of all compositions. The 1 kHz dissipation factor values in Ba-rich and stoichiometric samples were not observed to decrease with increasing fired density of the samples. High density samples of all three stoichiometries exhibited fairly small losses just above the Curie temperature, while Ba-rich and stoichiometric samples exhibited a marked decrease in the dissipation factor below 260 K.